fix: resolve Android MAUI app crash when opening URLs (#177)

src/NoteBookmark.BlazorApp.Tests/Helpers/BlazorTestContextExtensions.cs

@@ -17,6 +17,7 @@ public static BunitContext AddFluentUI(this BunitContext ctx)
     {
         ctx.JSInterop.Mode = JSRuntimeMode.Loose;
         ctx.Services.AddFluentUIComponents();
+        ctx.Services.AddScoped<NoteBookmark.SharedUI.IUrlLauncher, NoteBookmark.SharedUI.JsUrlLauncher>();
         return ctx;
     }
 

src/NoteBookmark.BlazorApp/Program.cs

@@ -10,7 +10,7 @@
 var builder = WebApplication.CreateBuilder(args);
 
 builder.AddServiceDefaults();
 builder.AddAzureTableClient("nb-tables");
 
 // Add HTTP client for API calls
 builder.Services.AddHttpClient<PostNoteClient>(client => 
@@ -19,6 +19,7 @@
             });
 builder.Services.AddTransient<IDataService>(sp => sp.GetRequiredService<PostNoteClient>());
 builder.Services.AddSingleton<ILocalHtmlCache, NoteBookmark.BlazorApp.AlwaysAvailableHtmlCache>();
+builder.Services.AddScoped<IUrlLauncher, JsUrlLauncher>();
 
 // Register server-side AI settings provider (direct database access, unmasked)
 builder.Services.AddScoped<AISettingsProvider>();

src/NoteBookmark.MauiApp.Tests/NoteBookmark.MauiApp.Tests.csproj

@@ -37,6 +37,7 @@
     <Compile Include="..\NoteBookmark.MauiApp\Data\ILocalHtmlStorageService.cs" Link="Data\ILocalHtmlStorageService.cs" />
     <Compile Include="..\NoteBookmark.MauiApp\Data\SyncService.cs" Link="Data\SyncService.cs" />
     <Compile Include="..\NoteBookmark.MauiApp\Data\SyncApiClient.cs" Link="Data\SyncApiClient.cs" />
+    <Compile Include="..\NoteBookmark.MauiApp\Data\MauiUrlLauncher.cs" Link="Data\MauiUrlLauncher.cs" />
   </ItemGroup>
 
   <ItemGroup>

src/NoteBookmark.MauiApp.Tests/UrlLauncherTests.cs

@@ -0,0 +1,53 @@
+using FluentAssertions;
+using Microsoft.JSInterop;
+using Moq;
+using NoteBookmark.MauiApp.Data;
+using NoteBookmark.SharedUI;
+using Xunit;
+
+namespace NoteBookmark.MauiApp.Tests;
+
+public class UrlLauncherTests
+{
+    [Fact]
+    public async Task JsUrlLauncher_WithNullOrWhitespaceUrl_DoesNotInvokeJs()
+    {
+        var jsMock = new Mock<IJSRuntime>();
+        var launcher = new JsUrlLauncher(jsMock.Object);
+
+        await launcher.OpenUrlAsync(null);
+        await launcher.OpenUrlAsync("   ");
+
+        jsMock.VerifyNoOtherCalls();
+    }
+
+    [Fact]
+    public async Task JsUrlLauncher_WithValidUrl_InvokesWindowOpen()
+    {
+        var jsMock = new Mock<IJSRuntime>();
+        jsMock.Setup(x => x.InvokeAsync<object>("open", It.IsAny<object[]>()))
+              .ReturnsAsync(null!);
+
+        var launcher = new JsUrlLauncher(jsMock.Object);
+
+        await launcher.OpenUrlAsync("https://example.com");
+
+        jsMock.Verify(x => x.InvokeAsync<object>("open", It.Is<object[]>(args =>
+            args.Length == 2 && (string)args[0] == "https://example.com" && (string)args[1] == "_blank"
+        )), Times.Once);
+    }
+
+    [Fact]
+    public async Task MauiUrlLauncher_WithNullOrInvalidUrl_DoesNotThrow()
+    {
+        var launcher = new MauiUrlLauncher();
+
+        var act1 = async () => await launcher.OpenUrlAsync(null);
+        var act2 = async () => await launcher.OpenUrlAsync("not-a-valid-url");
+        var act3 = async () => await launcher.OpenUrlAsync("https://example.com");
+
+        await act1.Should().NotThrowAsync();
+        await act2.Should().NotThrowAsync();
+        await act3.Should().NotThrowAsync();
+    }
+}

src/NoteBookmark.MauiApp/Data/MauiUrlLauncher.cs

@@ -0,0 +1,48 @@
+#if !NOT_MAUI
+using Microsoft.Maui.ApplicationModel.DataTransfer;
+#endif
+using NoteBookmark.SharedUI;
+
+namespace NoteBookmark.MauiApp.Data;
+
+public class MauiUrlLauncher : IUrlLauncher
+{
+#if !NOT_MAUI
+    private readonly IBrowser _browser;
+
+    public MauiUrlLauncher(IBrowser? browser = null)
+    {
+        _browser = browser ?? Browser.Default;
+    }
+#else
+    public MauiUrlLauncher()
+    {
+    }
+#endif
+
+    public async Task OpenUrlAsync(string? url)
+    {
+        if (string.IsNullOrWhiteSpace(url))
+        {
+            return;
+        }
+
+        if (!Uri.TryCreate(url, UriKind.Absolute, out var uri))
+        {
+            return;
+        }
+
+        try
+        {
+#if !NOT_MAUI
+            await _browser.OpenAsync(uri, BrowserLaunchMode.SystemPreferred);
+#else
+            await Task.CompletedTask;
+#endif
+        }
+        catch (Exception ex)
+        {
+            System.Diagnostics.Debug.WriteLine($"Failed to launch URL in MAUI browser: {ex.Message}");
+        }
+    }
+}

src/NoteBookmark.MauiApp/MauiProgram.cs

@@ -31,6 +31,7 @@ public static MauiHostingApp CreateMauiApp()
 #endif
 
         builder.Services.AddSingleton<Microsoft.Maui.Networking.IConnectivity>(Microsoft.Maui.Networking.Connectivity.Current);
+        builder.Services.AddSingleton<NoteBookmark.SharedUI.IUrlLauncher, NoteBookmark.MauiApp.Data.MauiUrlLauncher>();
 
         // Data Layer
         builder.Services.AddSingleton<NoteBookmark.MauiApp.Data.ILocalDataService, NoteBookmark.MauiApp.Data.LocalDataService>();

src/NoteBookmark.SharedUI/Components/Pages/Posts.razor

@@ -9,6 +9,7 @@
 @inject IDialogService DialogService
 @inject NavigationManager Navigation
 @inject ILocalHtmlCache localHtmlCache
+@inject IUrlLauncher urlLauncher
 @implements IDisposable
 
 <PageTitle>Posts</PageTitle>
@@ -130,7 +131,7 @@
 
     private async Task OpenUrlInNewWindow(string? url)
     {
-        await jsRuntime.InvokeVoidAsync("open", url, "_blank");
+        await urlLauncher.OpenUrlAsync(url);
     }
 
     private async Task CreateNoteForPost(string postId)

src/NoteBookmark.SharedUI/Components/Pages/Summaries.razor

@@ -5,6 +5,7 @@
 @inject IDataService client
 @inject NavigationManager Navigation
 @inject IJSRuntime jsRuntime
+@inject IUrlLauncher urlLauncher
 
 <PageTitle>Summaries</PageTitle>
 
@@ -49,6 +50,6 @@
 
     private async Task OpenUrlInNewWindow(string? url)
     {
-        await jsRuntime.InvokeVoidAsync("open", url, "_blank");
+        await urlLauncher.OpenUrlAsync(url);
     }
 }

src/NoteBookmark.SharedUI/Components/Pages/SummaryEditor.razor

@@ -10,6 +10,7 @@
 @inject IJSRuntime jsRuntime
 @inject IToastService toastService
 @inject SummaryService aiService
+@inject IUrlLauncher urlLauncher
 
 <h2>SummaryEditor</h2>
 
@@ -138,7 +139,7 @@ else{
 
     private async Task OpenUrlInNewWindow(string? url)
     {
-        await jsRuntime.InvokeVoidAsync("open", url, "_blank");
+        await urlLauncher.OpenUrlAsync(url);
     }
 
     private void AddExtraNote(string category)
@@ -273,5 +274,4 @@ else{
             isGenarating = false;
         }
     }
-
 }

src/NoteBookmark.SharedUI/IUrlLauncher.cs

@@ -0,0 +1,6 @@
+namespace NoteBookmark.SharedUI;
+
+public interface IUrlLauncher
+{
+    Task OpenUrlAsync(string? url);
+}

src/NoteBookmark.SharedUI/JsUrlLauncher.cs

@@ -0,0 +1,30 @@
+using Microsoft.JSInterop;
+
+namespace NoteBookmark.SharedUI;
+
+public class JsUrlLauncher : IUrlLauncher
+{
+    private readonly IJSRuntime _jsRuntime;
+
+    public JsUrlLauncher(IJSRuntime jsRuntime)
+    {
+        _jsRuntime = jsRuntime;
+    }
+
+    public async Task OpenUrlAsync(string? url)
+    {
+        if (string.IsNullOrWhiteSpace(url))
+        {
+            return;
+        }
+
+        try
+        {
+            await _jsRuntime.InvokeVoidAsync("open", url, "_blank");
+        }
+        catch
+        {
+            // Ignore JS interop exceptions when opening URL fails
+        }
+    }
+}